It’s completely possible to have a female death in a movie without it being “fridging.” For example, Jyn Erso in Rogue One - where her death is part of a sacrifice she makes to help the rebellion. Her death completes her character arc from aimless petty criminal to hero of the rebellion.

It’s a reference to a Green Lanteen comic, where a villain killed the hero’s girlfriend by literally stuffing her in a fridge. It’s now shorthand for killing off a wife or girlfriend to give the hero motivation.

Yeah, I’m with you on this. Deadpool spends the whole movie mocking comic book tropes but then leans hard on the Dead Girlfriend Motivation one to give the character depth. I didn’t think the film did near enough to satirize it, instead playing that very straight. (Also Wade and Vanessa have such great chemistry that…